Illuminating device for enlarging or projecting apparatus



Oct.,7, 1941. K. KALLUSCH ILLUMINATING DEVICE FOR ENLARGING 0RPROJECTING APPARATUS Filed April 20, 1939 [Qt V5 ro/P jfamzZZafiZZasck4Q fl/mewzz Patented Get. 7, 1941.

ILLUMINATING DEVICE FOR ENLARGING OR PROJECTING APPARATUS 'KamilloKallusch, Prerov, Czechoslovakia, as-

signor to Optikotechna, spolenost sr. o.,

Pi'erov, Prerov, Czech Czechoslovakia Application 'April 20. 1939,

In Czechoslovakia April 20,

oslovakia, a company of Serial No. 269,011 ma 3 Claims. (Cl. 88-24) Thepresent invention relates to a device for the direct electricalillumination of photographs or negatives for the purpose of permittingtheir reproduction in enlarging or projecting apparatus.

Such devices have hitherto consisted of a source of illuminationarranged in a special chamber which had to be cooled to a substan- Itial extent and consequently this entailed the use of apparatus ofrelatively large external di-. mens'ions. This increase in thedimensions of the illuminating chamber has been disadvanta- 'geousespecially in the case of enlarging apparatus of the smaller type.

Such drawbacks and disadvantages are avo ded by the illuminating deviceaccording to the present invention which comprises a casing including anilluminating'chamber, means associated with said chamber for permittinguniform illumination, and an incandescent electric lamp having the bulbthereof engaging partly'in said chamber and having the remainingpart ofsaid bulb exposed to cooling air.

That part of the electric lamp bulb which does not enter the saidchamber may be provided with coating means to prevent the entrance ofextraneous light rays which might act upon the sensitive photographicemulsion.

In order that the present invention may be clearly understood and feetthe same will now .be described more fully, by way of example, withreference to the accompanying drawing, in which:

Figure 1 is a sectional elevation of a device according to the presentinvention and Figure 2 is an elevation taken at right angles to Figure 1showing the device associated with enlarging apparatus suspended on aknown stand.

Referring to the drawing, i denotes the casing of the illuminatingdevice which is connected with an objective part it forms therewith asingle unit which is displaceably mounted on a guide 3 on which it isfixed in any desired position as by means of a set screw 4. The casing lis provided with openings 5 for the admission of cooling air and with anopening 6 for the insertion of a negative 1. Within the casing I isprovided a holder I having a flange l for fixing a condensing lensreadily carried into ef- 2 in such a manner that the illuminatingspace,is concave and is advantageously provided with a reflecting coating [3.

The socket I2 is provided with a circular opening through which thelower part it of the glass bulb of the incandescent electric lamppasses. The upper part i5 of the bulb is provided, above the socket andtherefore outside the illuminating space, with acoloured-e. g., opaldark red-or other coating which does not allow extraneous light rays topass through from the exterior of the apparatus, so that such rayscannot act upon the sensitive photographic emulsion. The said coatingmay comprise, alternatively, a metal casing provided with ribs on theexternal surface thereof for the purpose of better cooling and the like.The incandescent lamp is screwed into the customary socket it which issecured in a member i'l surrounding the upper part of the lamp andhaving side openings for the free admission of cooling air, the saidmember being applied to the socket II, or, if desired, fixed to theeashitherto employed, is cooled more completely than hitherto. Inaddition, there is obtained a i0 and also having one or more ventilatingopen- On the top edge of the holder I there is mounted a socket i! whichis made of a mat'erial of low conductivity. The inner surface of thesocket, which, with the holder I, encloses ing's ll'.

compact construction which permits ready access to all thecompone'ntparts.

What I claim is: 1

1. A device for direct illumination. in connection with a condensinglens housing of an enlarging or projecting apparatus, comprising acasing including an illuminating chamber, means i associated with saidchamber for permitting uni-- form illumination, an incandescent electriclamp having the bulb thereof engaging partly in said housing fortransmitting only'the direct rays to said condensing lens and having theremaining part of said bulb exposed to cooling air, and having a lightfiltered coating means on said remaining part of said bulb transparentto light rays inactive'for photographic sensitive emulsions.

2. A device for direct illumination in connection with the condensinglens housing of an enlarging or projecting apparatus, comprising acasing including an illuminating chamber, means associated with saidchamber for permitting uniform illumination, 9. socket at one end ofsaid chamber'having a concave surface at the inner side thereof, onincandescent electric lamp hav- 5 ing the bulb thereof engaging partlyin said tion with the condensing lens housing of an enlarging orprojecting apparatus, comprising a casing including an illuminatingchamber, means associated with said chamber for permitting uniformillumination, a socket at one end of said chamber having a concavesurface at the inner side thereof, 'said concave surface having areflecting surface, an incandescent electric lamp having the bulbthereof engaging partly in said 5 housing for transmitting\ only thedirect rays to said condensing lens and having the remaining 7 part ofsaid bulb exposed to cooling air and having a light filtered coatingmeans on said remaining part ofsaid bulb transparent to light 10 raysinactive for photographic sensitive emul- KAMILLO KALLUSC'H.

